[CentOS] premature question on 5.6

Mon Feb 7 16:05:55 UTC 2011
Brunner, Brian T. <BBrunner at gai-tronics.com>


> -----Original Message-----
> From: centos-bounces at centos.org 
> [mailto:centos-bounces at centos.org] On Behalf Of Jerry Geis
> Sent: Monday, February 07, 2011 10:55 AM
> To: CentOS ML
> Subject: [CentOS] premature question on 5.6
> What will be the correct way to migrate ext3 to ext4 going 
> from 5.5 to 5.6?
> Will something after the update ask if you want to migrate 
> the file systems?
> Looking forward to some file system speed ups with large files.

Google convert ext3 to ext4 centos

Hit 1: https://www.centos.org/modules/newbb/viewtopic.php?topic_id=26324
yum -y install e4fsprogs
vi /etc/fstab
(change ext3 to ext4 for my / partition)
mkinitrd --with=ext4 --with=ext3 -f /boot/initrd-2.6.18-194.3.1.el5.img
tune4fs -O extents,uninit_bg,dir_index /dev/mapper/VolGroup00-LogVolRoot
shutdown -r now
(reboot from DVD with linux rescue)
fsck -t ext4 -pf /dev/mapper/VolGroup00-LogVolRoot
(this failed for me so I had to then run...)
fsck -t ext4 -f /dev/mapper/VolGroup00-LogVolRoot
(answer Y to the questions about fixing it)
(reboot back into normal boot)

Hit 2: https://www.centos.org/modules/newbb/viewtopic.php?topic_id=26324
Entire page

Hit 3:
Using tune2fs should work just fine. There's a nice little guide at
http://ext4.wiki.kernel.org/index.ph...system_to_ext4 and a more
complete one at http://www.cyberciti.biz/tips/linux-...le-system.html

Hit 4: http://planet.admon.org/convert-file-system-from-ext3-to-ext4/
(the age of this hit is indeterminate, so the 'advice' to keep /boot in
ext3 is of unknown necessity)
Once you converted your file system to ext4, the fs cannot be mounted as
ext3. Note that ext4 may have some bugs so do not use it on productive
servers. It's also recommended that keep your /boot in ext3.

You need to check ext4 is supported and compiled in you current kernel.
Otherwise, you need to apply the patch, and re-compile your kernel. I
assume that your kernel supports ext4.
Simply follow these steps to convert an existing ext3 file-system to
ext4. For example, in order to converting /dev/sdb1 to ext4, you need to
# cd /; umount /dev/sdb1
# tune2fs -O extents,uninit_bg,dir_index /dev/sdb1
# fsck -pf /dev/sdb1

Now, all's OK, just mount it as ext4:

mount -t ext4 /dev/sdb1 /ext4

If you have converted /boot file system , you need to update
/boot/grub.conf. Use your favourite editor to open this file, find out
current kernel config section and append the following parameter:

Here is sample config:

title        Ubuntu 8.10, kernel
root        (hd0,1)
kernel    /boot/vmlinuz- ro quiet splash rootfstype=ext4
initrd        /boot/initrd.img-

Sounds pretty do-able.

This email and any files transmitted with it are confidential and
intended solely for the use of the individual or entity to whom
they are addressed. If you have received this email in error please
notify the system manager. This footnote also confirms that this
email message has been swept for the presence of computer viruses.
www.Hubbell.com - Hubbell Incorporated**